EP2238650B1

EP2238650B1 - Cable connector and cable clamp

Info

Publication number: EP2238650B1
Application number: EP08865965.1A
Authority: EP
Inventors: Jeroen De Bruijn; Nico Van Stiphout; Ton Karsmakers; Gert Droesbeke
Original assignee: FCI SA; Framatome Connectors International SAS
Current assignee: Amphenol FCI Asia Pte Ltd
Priority date: 2008-01-02
Filing date: 2008-12-17
Publication date: 2014-02-19
Anticipated expiration: 2028-12-17
Also published as: EP2238650A1; CN101933198A; CN101933198B; US20100285688A1; WO2009083461A1; US8342877B2

Description

FIELD OF THE DISCLOSURE

The present invention relates to the field of connectors, in particular electrical cable connectors.

BACKGROUND OF THE DISCLOSURE

In the field of connectors, in particular cable connectors, it is known to use a cable clamp, clamping the cable to the connector housing, for strain relief See for instance US 3858 960 , which discloses a cable connector according to the preamble of claim 1. Generally, the cable clamp is screwed to the housing. This requires screws, thus additional separate parts, and the screwing complicates assembly of the connector.
The connector housing and/or the cable clamp generally are formed providing an opening optimized for receiving a cable of a particular outer diameter and compressibility. Such connectors are not well suited for accommodating a cable of a different diameter and/or compressibility.
If the opening for the cable is small, portions of the cable may be pinched or crushed, which affects its transmissive and/or structural properties. This is in particular the case for cables for signal transmission, especially high speed signal transmission, and for multi-wire cables. Conversely, a large cable opening may allow slipping of the cable with respect to the housing, possibly affecting or compromising connections of and/or to the cable inside the housing. Thus, connectors having a cable clamp may have limited usefulness for many purposes. As a result, stocking and/or selling various sizes and types of connector housings and/or cable clamps for suitably clamping different cables is required. This substantially increases costs.
Therefore, a need exists for an improved cable connector reducing or alleviating the above-referenced problems.

SUMMARY OF THE DISCLOSURE

An object of the present invention is to provide a cable clamp that can be used for different cable diameters. This object is achieved with a cable connector according to claim 1. When the cable clamp is put in place in the housing, one of the two or more present locking means in the housing can be selected, depending on the type of cable to be clamped. This way, the position of the cable clamp can selectively be adjusted between at least two alternative clamping positions so it can be used for more than one cable diameter.
With only one slot of the two or more slots being used, the slots which have not been brought into engagement with the matching cable clamp extension, can for example be covered by a foil of electromagnetic shielding material. This prevents that the unused slot or slots forms a leak in the electromagnetic shielding. Alternatively, the slots can be replaced by blind holes.
The cable clamp extension forming the locking means comprise for example a hook.
To improve the grip of the cable clamp on the cable jacket, the intermediate portion of the cable clamp may be provided with one or more piercing teeth, e.g., piercing into the cable jacket. Optionally, the teeth may penetrate through the braid that has been folded back on the isolating jacket or sheath at the end of the cable, so as to bite into the isolating sheath so as to improve EMI shielding.
The intermediate portion can be provided with a flange bridging the gap between the intermediate portion and the adjacent edge of the cable receiving opening. The flange can be made of an electromagnetic shielding material.
In an alternative embodiment the intermediate cable clamp portion is provided with resilient teeth alternately folded in opposite directions. In use, the teeth resiliently clamp against the cable jacket. Such an arrangement of resilient teeth can effectively reduce freedom of forward movement of the clamped cable as well as backward movement.
In a further alternative embodiment, the intermediate section comprises at least two curved sections of different curving diameter. This way, the clamp can be used for stiffer cables having a diameter corresponding to one of the curved sections, and it can also be used for cables of larger diameter with higher compressibility.
Optionally, the intermediate cable clamp portion is provided with resilient teeth alternately folded in opposite directions to resiliently clamp against the cable jacket. Optionally, the intermediate portion of the cable clamp is provided with a series of outwardly bent shielding teeth, to cover the gap between the intermediate portion and the interior edge or wall of the cable opening and to complete the electromagnetic shielding. These teeth may have rounded end parts, e.g., be mushroom shaped, to maximize coverage of the gap between the cable clamp and the cable opening.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1:: shows in perspective view a connector according to the present invention;
Figure 2A:: shows in perspective view the interior of the connector of Figure 1;
Figure 2B:: shows in perspective view a multi-connector variant of the connector of Figure 2A;
Figure 3A:: shows a side view of the cable clamp of Figure 1;
Figure 3B:: shows a plan view of the cable clamp of Figure 1;
Figure 3C:: shows a perspective view of the cable clamp of Figure 1;
Figure 4:: shows a perspective view of a second embodiment of a connector according to the invention;
Figure 5A:: shows a perspective view of a cable clamp of the connector of Figure 4;
Figure 5B:: shows a side view of the cable clamp of Figure 5A;
Figure 6A:: shows a perspective view of a third embodiment of a connector according to the invention;
Figure 6B:: shows another perspective view of the connector of Figure 6A;
Figure 7A:: shows a perspective view of the cable clamp of the connector of Figure 6A;
Figure 7B:: shows a side view of the cable clamp of Figure 7A.

DETAILED DESCRIPTION OF EMBODIMENTS

Figure 1 shows in perspective view a cable connector 1 comprising a connector housing 2 and a cable clamp 3 for clamping a cable (not shown) to the housing 2.
The housing 2 is made of two matching casing sections 4, 5 both comprising a semi-circular collar section 6, 7 together forming a cylindrical collar 8 when both casing sections 4, 5 are joined together to form the housing 2. Figure 2 shows the interior of the connector 1 with the shell section 5 broken away. The collar 8 surrounds an opening 9 in the housing 2 for receiving a cable. In line with the collar 8 located within the housing 2 is a cable clamp 3, which is shown in more detail in Figures 3A - C.
The cable clamp 3 comprises a first mounting portion 11, a second mounting portion 12 aligned with respect to the first mounting portion, and a curved intermediate portion 13. The first mounting portion 11 has a rounded end and comprises an opening 14 allowing passage of a fixation screw, as shown in Figure 2. According to a preferred embodiment, the second mounting portion is provided with a bend portion or makes an angle with respect to the first mounting portion in order to make the mounting step easier.
The second mounting portion 12 forms a locking means provided with a slanting top edge 15.
The curved intermediate portion 13 has a concave side provided with five evenly distributed triangular teeth 16. On its convex side, the clamp 3 is provided with a collar or flange 17. To facilitate bending the flange 17, openings or slots 18 are provided on the folding line 19 of the flange 17.
The clamp 3 and the housing 2 are made of an electromagnetic shielding material.
The top side of the housing 2 is provided with locking means formed by slots 20, 21, both dimensioned to receive locking means 12 of the cable clamp 3. When the locking portion 12 is put into the first slot 20, the clamp leaves open a larger opening for passage of a cable than if portion 12 is put into the second slot 21. As a result, cables of different diameter can be clamped using the same cable clamp 3. If a smaller diameter cable is used, the cable clamp portion 12 is brought into engagement with slot 21. In that position, flange 17 covers the gap between the curved clamp portion 13 and the housing wall surrounding cable opening 9. Flange 17 can be made of an electro conductive material. The interior wall of the housing facing the flange 17 can be provided with projections or teeth contacting flange 17. This way, flange 17 completes the electromagnetic shielding of the connectors interior.
When a cable is clamped in the opening 9 by clamp 3, the triangular teeth 16 pierce into the cable jacket to give improved fixation of the cable. Optionally, the teeth penetrate through the braid that has been folded back on the isolating jacket or sheath ant the end of the cable, so as to bite into the isolating sheath so as to improve EMI shielding. Alternatively, the teeth penetrate through the isolating sheath to such extent that it contacts the underlying conductive shielding braid.
Slots 20, 21 may be dimensioned to limit passage of electromagnetic wavelengths above a particular cut-off wavelength of electromagnetic noise, corresponding to a lower frequency limit for EMI noise. Optionally, slots 20, 21 can be sealed with a foil of an electromagnetic shielding material. When the clamp portion 12 is brought into engagement with one of the slots, the corresponding seal is broken while the other slot remains sealed.
The slanting edge 15 of cable clamp portion 12 juts out off the slot 20, 21, allowing visual inspection, particularly if the portion 12 and the housing 2 have different colours, shades or brightness.
The opening 9 in housing 2 is provided with ribs or protrusions or teeth 22 to further reduce movement of the cable.
The cable to be used comprises electro conductive wires to be connected to contact points in a terminal block 23 closing off the housing 2.
In Figure 2B, a double connector is shown comprising a cable clamp 3A similar to the cable clamp in Figure 2A but with a larger flange 17A. A resilient fin 24 presses the flange 17A against the interior housing surface peripheral to the cable opening. Corner parts 25 with an L-shaped cross section surround the two side edges of the flange 17A, protecting the fin 24 from breaking when a certain force is exercised onto the cable and the cable clamp in the direction of fin 24.
A set of different exchangeable cable clamps can be used having different sizes of flanges. Clamps for cables of smaller diameter have to bridge a larger gap between the clamp and the cable opening edge and can for that purpose be provided with larger flanges. A set can for instance include the clamp 3 of Figure 2A and the clamp 3A of Figure 2B and optionally further type variations, wherein each clamp type can be used for two or more corresponding cable diameters.
Another embodiment of connector with a cable clamp 103 according to the present invention is shown in Figures 4 and 5A and 5B.
Figure 4 shows a housing 102 with an opening 109 for receiving a cable. In line with the opening 109 is a cable clamp 103, shown in detail in Figures 5A and 5B. The cable clamp 103 comprises a first portion 11 with an opening 114 allowing passage of a fixation screw, a second portion 112 provided with a hook 115, and a curved intermediate portion 113. End portions 111 and 112 are bent over right angles with the intermediate portion 113. On its concave side, the curved intermediate portion 113 is provided with teeth or leaf springs 116 alternately bent in opposite directions. The convex side of the curved portion 113 is provided with a series of mushroom shaped projections 117, bent under an angle of about 60 - 70 degrees relative to the intermediate portion 113.
When mounted in a connector housing and after connecting a cable to the connector, hook 115 of portion 112 is brought into engagement with a corresponding slot in the housing 2 and a fixation screw fixes the clamp via opening 114 in end portion 111. Teeth 116 resiliently clamp on the cable. Due to the alternating orientation of the teeth backward as well as forward movement of the cable is effectively reduced. The mushroom shaped projections 117 resiliently engage with the interior wall of opening 109, effectively bridging the gap between the cable clamp 113 and the interior wall of opening 109 and completing the electromagnetic shielding. The resiliency of the mushroom shaped projections 117 increases the range of cable diameters that can be used with the cable clamp 103.
A third embodiment of a cable clamp 203 according to which can be used in the connector of the invention is shown in Figures 6A - 7B. Figure 6A shows a triple cable connector having three cable openings 209 and cable clamps 203. As shown in detail in Figure 7A, the cable clamps 203 are provided with a first end portion 211 with an opening 204 for a fixation screw or similar fastening means, and a second end portion 212 with a hook 215. As shown in Figure 6B, hook 215 is mounted in a corresponding slot 220 in housing 202 of the connector. The cable clamp 203 has a curved intermediate section 213 having a profile with two rounded bulges of different diameter. Such a clamp can be used for stiffer cables having a diameter corresponding to either one of the bulges 222, 223, but also for more compressible cables with a larger diameter.
The described embodiments are intended to be illustrative rather than restrictive. Various modifications, variations and re-combinations of features of the embodiments as described can be made without departing from the scope of the claims.

Claims

Cable connector comprising a connector housing (2, 102, 202) with an opening for receiving a cable, and a cable clamp (3, 103, 203) mounted to the connector housing wherein the cable clamp comprises an curved intermediate section (13, 113, 213) between two or more mounting portions (11, 111, 211, 12, 112, 212), at least one of the mounting portions comprising locking means (12, 112, 212) for interlocking with one of at least two cooperative locking means of the housing (20, 21, 220), wherein the locking means of the connector housing comprises at least two slots (20, 21), each being dimensioned to interlock a matching locking means (12) of the cable clamp, characterized in these at least two locking slots are provided so that when the locking means (12) of the clamp is put into a first slot (20), the clamp leaves open a larger opening for passage of a cable than if the locking means (12) of the clamp is put into a second slot (20), thereby cables of different diameter can be clamped by said cable clamp.
Cable connector according to claim 1, wherein the clamp is located in the housing.
Cable connector according to claim 2 wherein the slot (20, 21), which has not been brought into engagement with the matching cable clamp extension, is covered by a foil of an electromagnetic shielding material.
Cable connector according to any one of claims 1 - 3 wherein the cable clamp locking means comprises a hook (112).
Cable connector according to any one of the preceding claims wherein the intermediate portion of the cable clamp is provided with piercing teeth.
Cable connector according to any one of the preceding claims wherein the intermediate portion is provided with a flange (17) bridging the gap between the intermediate portion (13) and the adjacent edge of the cable receiving opening (9).
Cable connector according to any one of the preceding claims wherein the intermediate cable clamp portion is provided with resilient teeth (116) alternatingly folded in opposite directions to resiliently clamp against the cable jacket.
Cable connector according to any one of the preceding claims wherein the intermediate section (213) comprises at least two curved sections (222, 223) of different curving diameter.